1. Introduction
The Flylin HDM66 HD Modulator is a versatile device designed to convert high-definition multimedia interface (HDMI) or analog audio/video (AV/RCA) signals into radio frequency (RF) signals. This allows for the distribution of video and audio content to multiple televisions or older TV sets via a standard coaxial cable network. The modulator supports both PAL and NTSC television formats, ensuring compatibility with various regional broadcasting standards. It is ideal for local CATV systems, commercial applications like hotels and conference rooms, or for integrating modern devices with older display technologies.
2. Safety Information
- Ensure the device is connected to a stable power source within the specified voltage range (DC 5V).
- Do not expose the device to water, moisture, or extreme temperatures.
- Avoid disassembling or modifying the device, as this may void the warranty and pose safety risks.
- Keep the device away from strong electromagnetic fields.
- Use only the provided or recommended power adapter.
3. Package Contents
Please check the package for the following items:
- Flylin HDM66 HD Modulator
- USB Power Cable
- User Manual
4. Product Overview
The HDM66 modulator features a compact design with clearly labeled ports for easy connection. It is built with quality plastic material for durability and long service life.
4.1 Device Layout and Ports

This image highlights the various ports and controls on the HDM66 modulator, including the LED light, ANT/RF input, RF output, A/V output, A/V RCA input, CH3/CH4 switch, and power on/off switch.
4.2 Dimensions

This image shows the physical dimensions of the Flylin HDM66 HD Modulator, measuring approximately 10.9cm (4.29in) in length, 7.1cm (2.79in) in width, and 3cm (1.18in) in height.
5. Setup and Connection
The HDM66 modulator offers flexible connection options for both HDMI and AV (RCA) sources.
5.1 Connecting an HDMI Source
- Connect your HDMI source device (e.g., TV box, game console, DVD player) to the HDMI INPUT port on the HDM66 modulator using an HDMI cable.
- Connect the RF OUTPUT port of the HDM66 modulator to the ANT IN or RF IN port of your television or RF splitter using a coaxial cable.
- Connect the provided USB power cable to the DC 5V INPUT port on the modulator and plug the other end into a USB power adapter (not included) or a compatible USB port.
- Ensure all connections are secure.

This diagram illustrates the connection of an HDMI source (like a game console or media player) to the HDM66 modulator, which then outputs an RF signal to a splitter, distributing the signal to several televisions.
5.2 Connecting an AV (RCA) Source
- Connect your AV source device (e.g., DVD player, VCR, CCTV system) to the A/V RCA INPUT ports (Yellow for Video, White for L-Audio, Red for R-Audio) on the HDM66 modulator using RCA cables.
- Connect the RF OUTPUT port of the HDM66 modulator to the ANT IN or RF IN port of your television or RF splitter using a coaxial cable.
- Connect the provided USB power cable to the DC 5V INPUT port on the modulator and plug the other end into a USB power adapter (not included) or a compatible USB port.
- Ensure all connections are secure.

This diagram demonstrates how to connect various RCA-enabled devices (like DVD players, PCs, or CCTV systems) to the HDM66 modulator, which then converts the signal for display on an older television via RF output.
6. Operating Instructions
- After making all necessary connections, power on the HDM66 modulator. The LED indicator should illuminate.
- On the modulator, select the desired output channel using the CH3/CH4 SWITCH. This determines the RF channel your TV will need to tune to.
- Select the appropriate TV format (PAL or NTSC) using the PAL/NTSC SWITCH based on your region's standard.
- Turn on your television and tune it to the corresponding channel (CH3 or CH4) that you selected on the modulator.
- The video and audio from your source device should now be displayed on your television.
7. Maintenance
- Cleaning: Use a soft, dry cloth to clean the exterior of the device. Do not use liquid cleaners or aerosols.
- Storage: When not in use for extended periods, store the device in a cool, dry place away from direct sunlight.
- Ventilation: Ensure the device has adequate ventilation and is not covered, to prevent overheating.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No picture or sound | No power to modulator; Incorrect TV channel selected; Loose cables; Incorrect input source on modulator. | Check power connection; Tune TV to CH3 or CH4; Ensure all cables are securely connected; Verify HDMI/AV source is active. |
| Poor picture quality (fuzzy, distorted) | Incorrect TV format (PAL/NTSC); Weak RF signal; Interference; Damaged cables. | Ensure PAL/NTSC switch matches your TV standard; Check cable quality and connections; Reduce interference from other electronic devices. |
| No audio, but picture is present | Incorrect audio cable connection (for AV); TV audio settings; Modulator audio settings. | For AV, ensure L-Audio (White) and R-Audio (Red) cables are correctly connected; Check TV audio input settings; Ensure modulator's sound system is compatible. |
9. Specifications

This table provides detailed technical specifications for the HDM66 modulator, including TV standard formats, frequency range, output level, input level, sound system, input/output ports, HDMI/HDCP versions, power consumption, operating temperature, and dimensions/weight.
| Item | HDM66 |
|---|---|
| TV Standard Formats | PAL/NTSC |
| Frequency Range | PAL: 55.25MHz/62.25MHz; NTSC: 61.25MHz/67.25MHz |
| Output Level | 75-85dBuV |
| Input Level | 0.77Vp-p for 80%+/-10% modulation |
| Sound System | M=4.5MHz, B/G=5.5MHz |
| Input Port | HDMI |
| Output Ports | RCA female |
| RF Input | Female |
| RF Output | Female |
| Input Resolution | 1080P/1080i/720P/576P/576i/480p |
| HDMI Version | 1.3 |
| HDCP Version | 1.3 |
| Power Consumption | 500mA (min) @5VDC |
| Operating Temperature | 0°C ~ +40°C |
| Dimension/Weight | 10.9*7.1*3.0cm/82g |
10. Warranty Information
Flylin products are designed and manufactured to the highest quality standards. This product is covered by a limited warranty against defects in materials and workmanship. Please retain your proof of purchase for warranty claims. For specific warranty terms and conditions, please refer to the documentation provided at the time of purchase or contact customer support.
11. Customer Support
If you encounter any issues or have questions regarding your Flylin HDM66 HD Modulator, please contact our customer support team. For the most up-to-date support information, including contact details, please visit the official Flylin website or refer to your product packaging.